硼对NiMo/γ-Al_2O_3加氢处理催化剂性能的影响

Effect of Boron Promoter on the Performance of NiMo/γ-Al_2O_3 Hydrotreating Catalyst

以不同硼质量分数改性γ-Al_2O_3为载体,采用等体积浸渍法制备了NiMo加氢处理催化剂。通过BET、TPD、XPS和HRTEM等技术对催化剂进行表征,以常三线柴油为原料油,考察催化剂的加氢脱氮和加氢脱硫活性。结果表明,随着硼质量分数的增加,载体的比表面积和孔体积逐渐减小,催化剂表面的中强酸量增加;提高了活性金属组分的硫化度以及催化剂表面活性组分原子浓度。硫化催化剂的MoS_2颗粒的堆积层数和片层长度也随着硼质量分数的增加而增加。硼的引入提高了催化剂的HDN活性,当硼质量分数为1.5%时,催化所得加氢脱氮率最高。硼的添加没有改善催化剂的HDS活性。

With Boron modifiedNiMo/γ-Al_2O_3 as carrier, a series of NiMo hydrotreating catalysts with different boron mass fractions were prepared by incipient-wetness impregnation method, and were characterized by BET, TPD, XPS and HRTEM techniques. The hydrodenitrogenation and hydrodesulfurization activities of these catalysts were tested with straight run gas oil （SRGO） diesel oil as raw material. The results showed that with the increase of the boron mass fraction, the specific surface area and the pore volume of the NiMo/γ-Al_2O_3 carrier gradually decreased, and the amount of intermediate strength acids on the catalyst surface increased. The sulfidity of the active metal component and the atomic concentration of the active component on the catalyst surface increased with the increase of the boron mass fraction. Stacked layers and slice length of MoS2 particles of the sulfide catalyst also increased with the boron mass fraction increasing. The introduction of boron improved the HDN activity of the catalyst. The hydrodenitrogenation rate of SRGO was the highest over the NiMo catalyst with the boron mass fraction of 1.5 %, compared with that of these tested NiMo catalysts. While, the increase of the boron mass fraction in the NiMo catalyst did not improve its HDS activity.